Merck gains ground in lung cancer with first-line combo approval

Keytruda wins FDA backing for all first-line NSCLC patients

Merck & Co has consolidated the position of its PD-1 inhibitor Keytruda in non-small cell lung cancer (NSCLC) with an FDA approval as a first-line therapy in combination with conventional chemotherapy.

The approval is significant because it means that immuno-oncology high-flier Keytruda (pembrolizumab) can be prescribed for all first-line NSCLC patients - regardless of how much their tumours express the biomarker PD-L1 - and this is expected to dramatically increase usage of the drug.

The accelerated approval is for the combination of Keytruda with pemetrexed/carboplatin and is the first for any anti-PD-1/PD-L1 therapy in this indication. It will lend additional momentum to Keytruda, which saw sales more than double to $584m in the first quarter of this year.

The new indication will allow Merck to pull even further away from its rivals in the market for checkpoint inhibitors in NSCLC, which analysts have suggested could be worth upwards of $10bn a year.

Merck already had FDA approval for Keytruda as an alternative to chemotherapy in patients with advanced NSCLC, getting a green light last October for use in patients whose tumours express high levels of PD-L1 (i.e. with 50% or more of the cells producing the biomarker).

At a stroke it overtook longstanding competitor Bristol-Myers Squibb in first-line NSCLC - as the latter's Opdivo (nivolumab) drug failed to show a benefit in a phase III trial reported last year - and with the new all-comer indication pulls even further ahead.

BMS' hopes of fighting back with a combination of Opdivo and CTLA4 inhibitor Yervoy (ipilimumab) in first-line NSCLC took a knock when it decided not to file for accelerated approval. The company has shrugged off the setbacks however Opdivo sales rose 60% to $1.1bn in the first three months of the year.

Merck is now thought to have a window of at least 9 to 12 months compared to Opdivo and other rivals including Roche's PD-L1 inhibitor Tecentriq (atezolizumab), which was approved for second-line NSCLC last October but isn't expected to have first-line data until early 2019.

Analysts at Leerink said recently however that there is a large number of combination studies of immuno-oncology drugs due to generate results in the coming months that could dramatically alter the ‘landscape’ of first-line NSCLC therapy. One example is AstraZeneca's combination of Imfinzi (durvalumab) and CTLA4 inhibitor tremelimumab due to generate first results in mid-2017 with survival data expected in 2018.

BMS' experience in first-line NSCLC - and Tecentriq's stunning failure in bladder cancer this week- show that fortunes can change rapidly in the immuno-oncology sector.